602 



GAS, HYDROCARBON 



passing backwards along tho upper chamber, and forwards along tho lower one, 

 becomes to a great extent decomposed into hydrogen, carbonic oxide, and carbonic 

 acid gases. The water-gas generated in tho retort A, as described above, enters the 

 lower chamber of the retort n, through tho connecting pipe c c, cast on tho mouthpiece. 

 In the chambers of this retort tho illuminating gas is generated, cither from coal, 

 cannel, resin, or other suitable material, and being rapidly carried forward by tho 

 current of water-gas, its illuminating principles are preserved from tho destruction 

 caused by prolonged contact with the incandescent surfaces in tho retort, whilst at tho 

 same time its volume is increased. When very rich cannols or other materials are 

 used, two, three, or even four water-gas retorts are made to discharge their gas into 

 the cannel retort. 



The hydrocarbon process has hitherto been applied only to resin, coals, and cannels. 

 The following is a brief summary of tho results of a series of experiments made by 

 Dr. Frankland on the manufacture of hydrocarbon resin-gas. Each hundredweight 

 of resin was dissolved by heat in 7i gallons of tho resin-oil of a former working, and 

 the liquid, whilst still hot, was run into one of the retorts, by means of a siphon tube, 

 in a stream about the thickness of a crowquill, whilst water-gas generated in the 

 second retort, was admitted, as described above. The mixed gases were then made 

 to stream through the usual form of condensing apparatus, and were afterwards com- 

 pelled to pass successively through wet and dry lime-puriiiers before they reached tho 

 gasholder. In order to secure a uniform mixture of the gas produced in each 

 experiment, it was allowed to remain at rest in the gasholder for at least twelve hours 

 before a specimen was withdrawn for analysis. 



In the following Tables both the practical and analytical results are given. 



I. Practical Results. 



Average production of gas per ton of resin . . . 32,080 cubic feet. 

 Average production of resin-oil per ton of resin . . 70'3 gallons. 

 Illuminating power of average gas before purification, as ascertained by shadow test, 

 75 cubic feet per hour = light of one short six spermaceti candle. 



II. Analytical Results. 



Amount of carbon-vapour contained in 1 volume of hydrocarbons = 2 '8 volumes. 



